External monitor support

[joevt]

Is there a Thunderbolt dock/port replicator that will support 3440x1440 @ 100hz, or even 75hz? I have a little USB-C port rep that is limited to 50hz and it's unusably laggy.

3440x1440@100Hz only requires DisplayPort 1.2 (four lanes of HBR2)
Any Thunderbolt dock/hub should allow that.

What USB-C dock do you have? A USB-C dock isn't going to work if it supports USB 3.x (probably like the one you have) unless it includes a DisplayPort 1.4 MST hub (like the CalDigit SOHO does) because such docks only have two lanes of DisplayPort. A DisplayPort 1.4 MST Hub can convert two lanes of HBR3 (optionally with DSC) to four lanes of HBR2. DSC is required for HDR or 100 Hz but Big Sur might not support DSC for MST hubs - it should work in Catalina.

A USB-C dock that supports USB only up to USB 2.0 (such as some made by CableMatters) can have four lanes of DisplayPort.

 

[Amethyst1]

A USB-C dock that supports USB only up to USB 2.0 (such as some made by CableMatters) can have four lanes of DisplayPort.

Yep. I use a CableMatters 201046 and can get 4K60, i.e. four-lane HBR2.

 

[mrgreen4242]

I have this one from Anker, https://us.anker.com/collections/hubs-docks/products/a8384. I would really like to have a single plug in option to get a bank of USB-A and C ports, ethernet, power, and video... sounds like it may not be possible.

EDIT: which is fine - I should be able to get a video adaptor that allow this, like the one that Amethyst1 posted, that takes up 1 port and then a USB port replicator that fits in the other. Then maybe I will connect the two USB cables with a little 3D printed part so it's the same "plug in one thing" experience."

Thanks for your help!

3440x1440@100Hz only requires DisplayPort 1.2 (four lanes of HBR2)
Any Thunderbolt dock/hub should allow that.

What USB-C dock do you have? A USB-C dock isn't going to work if it supports USB 3.x (probably like the one you have) unless it includes a DisplayPort 1.4 MST hub (like the CalDigit SOHO does) because such docks only have two lanes of DisplayPort. A DisplayPort 1.4 MST Hub can convert two lanes of HBR3 (optionally with DSC) to four lanes of HBR2. DSC is required for HDR or 100 Hz but Big Sur might not support DSC for MST hubs - it should work in Catalina.

A USB-C dock that supports USB only up to USB 2.0 (such as some made by CableMatters) can have four lanes of DisplayPort.

 

[Amethyst1]

I have this one from Anker, https://us.anker.com/collections/hubs-docks/products/a8384.

How are you connecting your display to that? Its HDMI port won’t do 3440x1440@100Hz.

 

[mrgreen4242]

How are you connecting your display to that? Its HDMI port won’t do 3440x1440@100Hz.

Yes that's the problem, lol. It's limited to 50hz, and it's terrible.

 

[joevt]

I have this one from Anker, https://us.anker.com/collections/hubs-docks/products/a8384.

It says it has a multifunction port that support 4K60. The HDMI only supports 4K30. The multifunction port is the USB-C port. Connect the display to the USB-C port.
This works because the Anker has two USB-C connections to the MacBook Pro. One connection is used for USB 3.x and 4K30 HDMI. The other connection is used for the multifunction port.

Otherwise, get a Thunderbolt dock.

 

[Amethyst1]

Yes that's the problem, lol. It's limited to 50hz, and it's terrible.

It also has a USB-C port with DisplayPort Alternate Mode. Connect the display to that. If your display only has a DisplayPort input, a USB-C to DisplayPort cable will do the trick.

 

[mrgreen4242]

It says it has a multifunction port that support 4K60. The HDMI only supports 4K30. The multifunction port is the USB-C port. Connect the display to the USB-C port.
This works because the Anker has two USB-C connections to the MacBook Pro. One connection is used for USB 3.x and 4K30 HDMI. The other connection is used for the multifunction port.

Otherwise, get a Thunderbolt dock.

It also has a USB-C port with DisplayPort Alternate Mode. Connect the display to that. If your display only has a DisplayPort input, a USB-C to DisplayPort cable will do the trick.

Ah, thank you both! Still might need to get a different dock since this leaves me with 0 USB-C ports.

 

[MFJones]

I got my M1 MBA today and tested it with the Dell D6000 DisplayLink hub.

I have a 24" monitor connected with HDMI and a 32" monitor connected with HDMI-->DisplayPort. The hub is one USB-C connection and provides dual monitors (up to 3 in 4K), audio, power, and several USB-A connections.

To get it working I had to download the DisplayLink drivers for macOS.

The displays look fine and feel like normal. I was able to play YouTube videos and couldn't tell the difference.

It preserved my display arrangement when I unplugged and plugged back in.

Overall, it's a decent solution and I have no complaints, though I would still prefer if the M1 chip is able to natively support multiple displays.

I'm having an issue that i'm hoping someone smarter than me can help me solve because it is incredibly annoying. I am using an M1 pro MBP with the Dell D6000 dock to connect to two identical Dell UltraSharp 32 4K USB-C Monitors - U3219Q. I am connecting the monitors to the dock with 4k 60hz Display Port to Display Port connections.

I have downloaded the Dell Display manager and Display Link Manager software and I can display everything to the monitors but I have one glaring concern. The native display resolution is far too small to be usable. When I go into the scaling options, however, instead of seeing you usually see for Mac OS scaling options (more space, larger text, etc.), it only gives me the actual resolution options (1920 x 1080, 3840 x 2160, etc.).

The only resolution that is somewhat usable and not either way too small or fuzzy and not scaled to the full screen appropriately is 1920 x 1080 but that is too far in the other direction and is far too large.

If i connect to a Kensington SD4900P dock, I have another set of issues (only one of the monitors will show up so i have to connect one of them natively via USB-C and only run one through the dock), but I do get the traditional scaling options and it is much more usable in terms of the scaling working appropriately.

Does anyone know if the scaling option issue is just a problem with the D6000 compatibility with OSX or if there is something else I can do to solve this that I haven't yet come across?

 

[Delarock]

try switchressx and choose there some suitable resolution in HDPI mode

 

[petterihiisila]

I'm having an issue that i'm hoping someone smarter than me can help me solve because it is incredibly annoying. I am using an M1 pro MBP with the Dell D6000 dock to connect to two identical Dell UltraSharp 32 4K USB-C Monitors - U3219Q. I am connecting the monitors to the dock with 4k 60hz Display Port to Display Port connections.

I have downloaded the Dell Display manager and Display Link Manager software and I can display everything to the monitors but I have one glaring concern. The native display resolution is far too small to be usable. When I go into the scaling options, however, instead of seeing you usually see for Mac OS scaling options (more space, larger text, etc.), it only gives me the actual resolution options (1920 x 1080, 3840 x 2160, etc.).

The only resolution that is somewhat usable and not either way too small or fuzzy and not scaled to the full screen appropriately is 1920 x 1080 but that is too far in the other direction and is far too large.

If i connect to a Kensington SD4900P dock, I have another set of issues (only one of the monitors will show up so i have to connect one of them natively via USB-C and only run one through the dock), but I do get the traditional scaling options and it is much more usable in terms of the scaling working appropriately.

Does anyone know if the scaling option issue is just a problem with the D6000 compatibility with OSX or if there is something else I can do to solve this that I haven't yet come across?

Those are huge monitors and need a very granular HiDPI resolution selection to become perfect. macOS won't give you the best choices by default, as you've seen.

SwitchResX is not likely to offer that choice on M1 either, based on what other people with 4k have said. Not with HiDPI rendering anyway.

BetterDummy is currently the best solution, though it has some shortcomings, it's free software under heavy development. But it gets the job done, you'll get dozens of HiDPI resolutions to choose from. Take your time to learn how to set it up. Most users seem to be happy with it, once set up correctly.

The main shortcoming is that macOS fails to apply some gestures correctly on mirrored displays. And this workaround requires mirroring. Swiping between desktops will only work for the main screen. Sideways 4-finger swipe on any display will always switch the main screen desktop. I'm talking about Mission Control and multiple virtual desktops per monitor. All other gestures seem to work OK.

 

[MFJones]

Those are huge monitors and need a very granular HiDPI resolution selection to become perfect. macOS won't give you the best choices by default, as you've seen.

SwitchResX is not likely to offer that choice on M1 either, based on what other people with 4k have said. Not with HiDPI rendering anyway.

BetterDummy is currently the best solution, though it has some shortcomings, it's free software under heavy development. But it gets the job done, you'll get dozens of HiDPI resolutions to choose from. Take your time to learn how to set it up. Most users seem to be happy with it, once set up correctly.

The main shortcoming is that macOS fails to apply some gestures correctly on mirrored displays. And this workaround requires mirroring. Swiping between desktops will only work for the main screen. Sideways 4-finger swipe on any display will always switch the main screen desktop. I'm talking about Mission Control and multiple virtual desktops per monitor. All other gestures seem to work OK.

Thanks. the interesting thing is that the OSX standard scaling options (the little boxes that say more space or larger text, etc.) work fine with the monitors using a Kensington dock, but those scaling options are not available using the Dell dock.

 

[joevt]

I'm having an issue that i'm hoping someone smarter than me can help me solve because it is incredibly annoying. I am using an M1 pro MBP with the Dell D6000 dock to connect to two identical Dell UltraSharp 32 4K USB-C Monitors - U3219Q. I am connecting the monitors to the dock with 4k 60hz Display Port to Display Port connections.

I have downloaded the Dell Display manager and Display Link Manager software and I can display everything to the monitors but I have one glaring concern. The native display resolution is far too small to be usable. When I go into the scaling options, however, instead of seeing you usually see for Mac OS scaling options (more space, larger text, etc.), it only gives me the actual resolution options (1920 x 1080, 3840 x 2160, etc.).

The only resolution that is somewhat usable and not either way too small or fuzzy and not scaled to the full screen appropriately is 1920 x 1080 but that is too far in the other direction and is far too large.

If i connect to a Kensington SD4900P dock, I have another set of issues (only one of the monitors will show up so i have to connect one of them natively via USB-C and only run one through the dock), but I do get the traditional scaling options and it is much more usable in terms of the scaling working appropriately.

Does anyone know if the scaling option issue is just a problem with the D6000 compatibility with OSX or if there is something else I can do to solve this that I haven't yet come across?

If you have an M1 Pro or M1 Max, then you should be using a Thunderbolt hub or dock to connect two displays (supports two 4-lane DisplayPort connections, 4K60 10bpc RGB for each).

D6000 uses DisplayLink which means it uses USB for the display instead of the GPU. USB is not as fast and has compression. DisplayLink will be missing scaling options.

SD4900P uses DisplayLink for two displays and DisplayPort Alt Mode for a third display (but only two lanes of DisplayPort). Maybe scaling works because you were using DisplayPort Alt Mode? The display may be limited to 30Hz in that case because the DisplayPort connection only has two lanes. Did you have DisplayLink drivers for the other display?

I wonder if BetterDummy works with DisplayLink?
https://github.com/waydabber/BetterDummy

 

[MFJones]

try switchressx and choose there some suitable resolution in HDPI mode

thanks, will try!

 

[MFJones]

If you have an M1 Pro or M1 Max, then you should be using a Thunderbolt hub or dock to connect two displays (supports two 4-lane DisplayPort connections, 4K60 10bpc RGB for each).

D6000 uses DisplayLink which means it uses USB for the display instead of the GPU. USB is not as fast and has compression. DisplayLink will be missing scaling options.

SD4900P uses DisplayLink for two displays and DisplayPort Alt Mode for a third display (but only two lanes of DisplayPort). Maybe scaling works because you were using DisplayPort Alt Mode? The display may be limited to 30Hz in that case because the DisplayPort connection only has two lanes. Did you have DisplayLink drivers for the other display?

I wonder if BetterDummy works with DisplayLink?
https://github.com/waydabber/BetterDummy

Do you know of any TB docks that would work better with an M1 for 2-3 4k displays vs. the D6000 or SD4900P?

 

[joevt]

Do you know of any TB docks that would work better with an M1 for 2-3 4k displays vs. the D6000 or SD4900P?

Most any Thunderbolt dock can do 1 (original M1) or 2 displays (M1 Pro or M1 Max). Then for additional displays just connect a USB DisplayLink adapter to the dock. Of course, if you have an M1 Max then add a second Thunderbolt dock for two more displays and only use DisplayLink if you want 5 or more displays.

 

[MFJones]

try switchressx and choose there some suitable resolution in HDPI mode

So I tried switchresx and unless I'm doing something wrong, I'm not finding a resolution that is as crisp as the standard scaling options that are usually available through OSX. I'm not sure why they show up as available with Kensington dock but they are not available with the dell dock but maybe it's a compatibility issue with dell and I'm beating my head against the wall.

 

[MFJones]

If you have an M1 Pro or M1 Max, then you should be using a Thunderbolt hub or dock to connect two displays (supports two 4-lane DisplayPort connections, 4K60 10bpc RGB for each).

D6000 uses DisplayLink which means it uses USB for the display instead of the GPU. USB is not as fast and has compression. DisplayLink will be missing scaling options.

SD4900P uses DisplayLink for two displays and DisplayPort Alt Mode for a third display (but only two lanes of DisplayPort). Maybe scaling works because you were using DisplayPort Alt Mode? The display may be limited to 30Hz in that case because the DisplayPort connection only has two lanes. Did you have DisplayLink drivers for the other display?

I wonder if BetterDummy works with DisplayLink?
https://github.com/waydabber/BetterDummy

I ended up giving up on both the Dell and Kensington docks. I ordered a CalDigit Element Thunderbolt 4 hub and it works perfectly. No lag, proper scaling options. It is compact and has a very small footprint and looks great on the desk. if you don't need ethernet/SD card options, I could not recommend more. Solved all of my issues.

 

[Creole Ned]

I'm wondering if anyone can help with my particular DisplayLink setup. I'm not sure if I have bad hardware or am just missing something really obvious.

The hardware I have:

• MacBook Air M1
• Two Asus VG27A 27" monitors
• CalDigit TS3 Plus dock
• StarTech USB to HDMI DisplayLink adapter

I have the monitors connected like so:

• Monitor 1: Connected via HDMI to USB-C cable to CalDigit dock
• Monitor 2: Connected via HDMI to USB-A DisplayLink adapter to CalDigit dock

I have run both the latest DisplayLink drivers, and the beta drivers that support rotation.

What happens in this setup is if I have the DisplayLink adapter disconnected, the other monitor (connected by a USB-C to HDMI cable) works fine. Likewise, if I unplug the monitor connected by the USB-C to HDMI cable, the DisplayLink monitor works fine.

If both are connected, only the DisplayLink-connected monitor will work. The DisplayLink menu bar app will show that both monitors are functioning, but the display in the second one will remain blank.

I've tried moving cables around and other stuff, to no avail. This also happens if I bypass the dock and connect the DisplayLink adapter to the Air directly (using a USB-C to USB-A adapter).

My questions:

1. Is this happening because both monitors are connecting via HDMI? Would it work if one was connected via DisplayPort instead?
2. Is the StarTech adapter misbehaving?
3. Driver shenanigans?
4. Did I hurt a monitor in a past life, and this is its revenge?

My original plan was to get rid of my Air and get an M1 Mac mini, since I don't currently need a laptop, but I then thought it would be cheaper and easier to use the DisplayLink adapter instead. If, you know, it worked!

Any help/advice is appreciated.